langchain[patch]: Migrate output parsers to support optional community imports (#21103)

Migrate output parsers

libs/langchain/langchain/output_parsers/__init__.py

@@ -12,6 +12,8 @@
 
     Serializable, Generation, PromptValue
 """  # noqa: E501
+from typing import TYPE_CHECKING, Any
+
 from langchain_core.output_parsers import (
     CommaSeparatedListOutputParser,
     ListOutputParser,
@@ -26,6 +28,7 @@ from langchain_core.output_parsers.openai_tools import (
     PydanticToolsParser,
 )
 
+from langchain._api import create_importer
 from langchain.output_parsers.boolean import BooleanOutputParser
 from langchain.output_parsers.combining import CombiningOutputParser
 from langchain.output_parsers.datetime import DatetimeOutputParser
@@ -39,6 +42,24 @@ from langchain.output_parsers.retry import RetryOutputParser, RetryWithErrorOutp
 from langchain.output_parsers.structured import ResponseSchema, StructuredOutputParser
 from langchain.output_parsers.yaml import YamlOutputParser
 
+if TYPE_CHECKING:
+    from langchain_community.output_parsers.rail_parser import GuardrailsOutputParser
+
+# Create a way to dynamically look up deprecated imports.
+# Used to consolidate logic for raising deprecation warnings and
+# handling optional imports.
+DEPRECATED_LOOKUP = {
+    "GuardrailsOutputParser": "langchain_community.output_parsers.rail_parser"
+}
+
+_import_attribute = create_importer(__package__, deprecated_lookups=DEPRECATED_LOOKUP)
+
+
+def __getattr__(name: str) -> Any:
+    """Look up attributes dynamically."""
+    return _import_attribute(name)
+
+
 __all__ = [
     "BooleanOutputParser",
     "CombiningOutputParser",

libs/langchain/langchain/output_parsers/ernie_functions.py

@@ -1,10 +1,40 @@
-from langchain_community.output_parsers.ernie_functions import (
+from typing import TYPE_CHECKING, Any
-    JsonKeyOutputFunctionsParser,
+
-    JsonOutputFunctionsParser,
+from langchain._api import create_importer
-    OutputFunctionsParser,
+
-    PydanticAttrOutputFunctionsParser,
+if TYPE_CHECKING:
-    PydanticOutputFunctionsParser,
+    from langchain_community.output_parsers.ernie_functions import (
-)
+        JsonKeyOutputFunctionsParser,
+        JsonOutputFunctionsParser,
+        OutputFunctionsParser,
+        PydanticAttrOutputFunctionsParser,
+        PydanticOutputFunctionsParser,
+    )
+
+# Create a way to dynamically look up deprecated imports.
+# Used to consolidate logic for raising deprecation warnings and
+# handling optional imports.
+DEPRECATED_LOOKUP = {
+    "JsonKeyOutputFunctionsParser": (
+        "langchain_community.output_parsers.ernie_functions"
+    ),
+    "JsonOutputFunctionsParser": "langchain_community.output_parsers.ernie_functions",
+    "OutputFunctionsParser": "langchain_community.output_parsers.ernie_functions",
+    "PydanticAttrOutputFunctionsParser": (
+        "langchain_community.output_parsers.ernie_functions"
+    ),
+    "PydanticOutputFunctionsParser": (
+        "langchain_community.output_parsers.ernie_functions"
+    ),
+}
+
+_import_attribute = create_importer(__package__, deprecated_lookups=DEPRECATED_LOOKUP)
+
+
+def __getattr__(name: str) -> Any:
+    """Look up attributes dynamically."""
+    return _import_attribute(name)
+
 
 __all__ = [
     "JsonKeyOutputFunctionsParser",

libs/langchain/langchain/output_parsers/rail_parser.py

@@ -1,5 +1,25 @@
-from langchain_community.output_parsers.rail_parser import (
+from typing import TYPE_CHECKING, Any
-    GuardrailsOutputParser,
-)
 
-__all__ = ["GuardrailsOutputParser"]
+from langchain._api import create_importer
+
+if TYPE_CHECKING:
+    from langchain_community.output_parsers.rail_parser import GuardrailsOutputParser
+
+# Create a way to dynamically look up deprecated imports.
+# Used to consolidate logic for raising deprecation warnings and
+# handling optional imports.
+DEPRECATED_LOOKUP = {
+    "GuardrailsOutputParser": "langchain_community.output_parsers.rail_parser"
+}
+
+_import_attribute = create_importer(__package__, deprecated_lookups=DEPRECATED_LOOKUP)
+
+
+def __getattr__(name: str) -> Any:
+    """Look up attributes dynamically."""
+    return _import_attribute(name)
+
+
+__all__ = [
+    "GuardrailsOutputParser",
+]